A niche form of pop music that is appreciated by people who don't like jazz. They think it sounds cool to be a smooth jazz listener and don't realize that it's not jazz at all. To paraphrase Mark Twain, the difference between jazz and smooth jazz is like the diffference between lightning and a lightning bug.

She claims to like jazz but anything other than smooth jazz is too far out for her.

A musical genre characterized by bland instrumental watered-down jazz; the soundtrack for men inbetween mid-life-crisises.
Every city has a radio station devoted to this brand of ambient droning -- usually called "The Oasis."

Was it just me, or was that elevator ride made more enjoyable by the smooth jazz stylings played at a reasonable volume?

Instrumental pop music that gives jazz a bad name. Only referred to as jazz because many of the people that play it are saxophone players, and as soon as something is played on a saxophone, you can automatically sell it as "jazz" to the general public because many people can't tell the difference. They simply hear something played on a saxophone and automatically categorize it as jazz.

Person 1: I play saxophone. Most of the stuff I play is jazz.
Person 2: Oh, you mean smooth jazz, like Kenny G?
Person 1: NO! I mean real jazz, like Charlie Parker, Lester Young, John Coltrane, and Wayne Shorter.